/*
 * jPOS Project [http://jpos.org]
 * Copyright (C) 2000-2015 Alejandro P. Revilla
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.jpos.iso;

import java.io.IOException;
import java.io.InputStream;


/**
 * ISOFieldPackager Binary Hex Fixed LLBINARY
 *
 * @author apr@cs.com.uy
 * @version $Id$
 * @see ISOComponent
 */
public class IFB_LLHFBINARY extends ISOFieldPackager {
	public IFB_LLHFBINARY() {
		super();
	}

	/**
	 * @param len         - field len
	 * @param description symbolic descrption
	 */
	public IFB_LLHFBINARY(int len, String description) {
		super(len, description);
	}

	/**
	 * @param c - a component
	 * @return packed component
	 * @throws ISOException
	 */
	public byte[] pack(ISOComponent c) throws ISOException {
		int len = ((byte[]) c.getValue()).length;
		if (len > getLength() || len > 255) {
			throw new ISOException(
					"invalid len " + len + " packing field " + c.getKey()
			);
		}
		byte[] b = new byte[getLength() + 1];
		b[0] = (byte) len;
		System.arraycopy(c.getValue(), 0, b, 1, len);
		return b;
	}

	/**
	 * @param c      - the Component to unpack
	 * @param b      - binary image
	 * @param offset - starting offset within the binary image
	 * @return consumed bytes
	 * @throws ISOException
	 */
	public int unpack(ISOComponent c, byte[] b, int offset) throws ISOException {
		int len = b[offset] & 0xFF;
		byte[] value = new byte[len];
		System.arraycopy(b, ++offset, value, 0, len);
		c.setValue(value);
		return getLength() + 1;
	}

	public void unpack(ISOComponent c, InputStream in)
			throws IOException, ISOException {
		byte[] b = readBytes(in, 1);
		int len = b[0] & 0xFF;
		c.setValue(readBytes(in, len));
		in.skip(getLength() - len);
	}

	public ISOComponent createComponent(int fieldNumber) {
		return new ISOBinaryField(fieldNumber);
	}

	public int getMaxPackedLength() {
		return getLength() + 1;
	}
}

